Optical package substrate and optical device

ABSTRACT

There is provided an optical package substrate and a molding method therefor, which provides for easy production, easy mounting of optical elements such as photodiodes and lasers, good functionality, productivity, and economy, as well as an optical device incorporating the package substrate. On the surface of an optical package substrate  11 , a guide groove  12  used for the positioning of an optical fiber and a tapered face  13  adjoining the guide groove  12  are provided, the tapered face  13  being formed so as to have a predetermined angle. A mirror  17  for reflecting light is formed on the tapered face  13 . An optical fiber  15  is affixed in the guide groove  12 . Above the tapered face  13  is mounted a surface reception type photodiode  16 , which is placed in a position for receiving light deflected by the mirror  17  provided on the tapered face  13 . By providing a positioning marker (not shown) for a light receiving element on the optical package substrate  11 , it becomes particularly easy to mount the surface reception type photodiode  16  through passive alignment.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to an optical package substrate andan optical device, and more particularly to a package substrate having asurface configuration suitable for mounting optical components and/oroptical elements thereon, and a molding method for such a packagesubstrate; and an optical device constructed by employing the packagesubstrate.

[0003] 2. Description of the Background Art

[0004] Optical communication systems employing optical fibers areevolving themselves from conventional long haul communication systemsinto subscriber communication systems. Subscriber-type opticalcommunication systems require the use of small and inexpensive opticaldevices.

[0005] In conventional optical devices, optical components such asoptical fibers and/or lenses and optical elements such as lasers and/orphotodiodes are deployed in a coaxial arrangement. Usually, thepositioning of optical fibers and lenses requires a high precision,e.g., a tolerance of ±1 μm. Therefore, a so-called active alignmenttechnique has been used for the assembly of an optical device, where thepositioning of the components is adjusted while driving the opticalelements with laser light actually being led therethrough. However, thistechnique requires complicated tasks, and is time-consuming, thuspresenting a substantial cost problem.

[0006] On the other hand, so-called passive alignment, in which thecomponents are positioned without the aforementioned adjustment hasattracted attention as a technique for simplifying the assembly of anoptical device. Typical examples of this technique are used in opticaldevices such that light guided through optical fibers and opticalcavities is deflected by 90° so as to be received by a photodiode of asurface reception type. Various ideas have been proposed for thistechnique, in documents such as Japanese Patent Laid-Open PublicationNo. 11-326662 and Japanese Patent No. 2687859.

[0007]FIG. 19 is a cross-sectional view showing an exemplary opticaldevice structure which utilizes a conventionally-proposed deflectionmethod.

[0008] As shown in FIG. 19, an end face of an optical fiber (or anoptical waveguide) 191 is ground at 45°, with a reflection mirror 192being provided on this end face. Light guided through the optical fiber(optical waveguide) 191 which is incident from the left direction inFIG. 19 has its optical path turned (i.e., deflected) by 90° at themirror 192, so as to be received by the photodiode 193. The photodiode193 may be of a surface reception type as that shown in FIG. 19, or of adifferent type called a “waveguide type”.

[0009] A surface reception type photodiode has a large area forreceiving light, so that it only requires a positioning precision ofonly about ±tens of microns (μm) with respect to an optical fiber or anoptical waveguide. Therefore, the mounting of a surface reception typephotodiode can be realized through a passive alignment, which involvesforming markers on the substrate as reference points for the mountingprocess. However, when light which is guided through the optical fiberor optical waveguide needs to be received directly at the front face ofthe surface reception type photodiode, it is necessary to mount thesurface reception type photodiode in an upright position on thesubstrate, which makes mass production more difficult. An example ofthis situation is monitoring of a laser output, where surface receptiontype photodiodes are a common choice.

[0010] On the other hand, a waveguide type photodiode has a lightreceiving layer on the order of several microns. Therefore, apositioning precision as stringent as ±1 μm is required in order toensure that light guided through an optical fiber or optical waveguideis properly coupled to a waveguide type photodiode. Thus, activealignment is usually employed for waveguide type photodiodes, therebypresenting a substantial mounting cost problem.

[0011] Thus, it can be seen that the construction shown in FIG. 19,where light which exits from an optical fiber or optical waveguide isdeflected by 90°, can be highly effective in terms of mass productionand mounting costs, because it makes it possible to mount a surfacereception type photodiode in a face-down manner through passivealignment.

[0012]FIG. 20 shows another exemplary optical device structure utilizingthe conventional deflection method described in Japanese PatentLaid-Open Publication No. 11-326662.

[0013] Referring to FIG. 20, this optical device features a reflectivemember 201, which is formed by processing a portion of an opticalwaveguide into a reflective surface for reflecting light. Light which ispropagated through the waveguide layer 202 to exit at its end face isdeflected by 90°, so as to be received by a surface reception typephotodiode 203.

[0014] As illustrated by the above two examples, conventional opticaldevice structures are based on the concept of deflecting an optical pathof light exiting from an optical fiber or optical waveguide so as toallow the exiting light to be received by a surface reception typephotodiode, which requires a relatively low receiving positioningprecision, with a view to reducing the device cost.

[0015] However, the conventional optical device structures illustratedin FIGS. 19 and 20 require an additional process of working an end faceof an optical fiber (or an optical waveguide) into a face having a 45°slope. Moreover, in order to minimize the scattering loss at theprocessed surface, it is essential to secure a high planar precision, sothat processes such as grinding, dry etching, wet etching, and cuttingmust be carried out with a good reproducibility. Especially in the casewhere an optical fiber processed so as to have a slanting end face isemployed, light exiting from the optical fiber may not be properlyincident on a photodiode if the optical fiber fails to be mounted in thecorrect orientation, due to rotation or the like.

[0016] Thus, while conventional optical device structures provideadvantages associated with simplified photodiode mounting, they alsorequire additional processing steps, which detract from the costadvantages.

SUMMARY OF THE INVENTION

[0017] Therefore, the objectives of the present invention are to providean easy-to-manufacture optical package substrate which allows for easymounting of optical elements such as photodiodes and lasers, and whichis excellent in functionality, producibility, and economy, and a moldingmethod for such an optical package substrate; and to provide an opticaldevice constructed by employing the package substrate.

[0018] The present invention has the following features to attain theabove object.

[0019] A first aspect of the present invention is directed to an opticalpackage substrate for mounting an optical component and/or an opticalelement thereon, comprising: a guide section for fixing an optical axisof an optical fiber mounted in the guide section, the guide sectionbeing a groove formed on a surface of a substrate and extending from anend face of the substrate to a predetermined portion of the substrate;and an optical path deflection section for deflecting an optical path byreflection, the optical path deflection section being formed at thepredetermined portion of the guide section so as to be in a positionintersecting the optical axis of the optical fiber mounted in the guidesection.

[0020] Thus, according to the first aspect, a guide section used for thepositioning of an optical fiber, and an optical path deflection sectionfor deflecting light through reflection are concurrently molded onto anoptical package substrate. As a result, a passive alignment of anoptical component and an optical element can be easily realized withoutrequiring any additional processing steps.

[0021] A second aspect according to the present invention is directed toan optical package substrate for mounting an optical component and/or anoptical element thereon, comprising: a waveguide section as a grooveformed on a surface of a substrate and extending from an end face of thesubstrate to a predetermined portion of the substrate, the waveguidesection corresponding to a predetermined optical waveguide core pattern;and an optical path deflection section for deflecting an optical path byreflection, the optical path deflection section being formed at thepredetermined portion of the waveguide section so as to be in a positionintersecting an optical axis of the optical waveguide defined in thewaveguide section.

[0022] Thus, according to the second aspect, a waveguide sectioncorresponding to an optical waveguide core pattern and an optical pathdeflection section for deflecting light through reflection areconcurrently molded onto an optical package substrate. As a result, apassive alignment of an optical component and an optical element can beeasily realized without requiring any additional processing steps.

[0023] A third aspect according to the present invention is directed toan optical package substrate for mounting an optical component and/or anoptical element thereon, comprising: a stage portion for fixing anoptical axis of a light receiving/emitting element mounted on the stageportion, the stage portion being formed on a surface of a substrate; andan optical path deflection section for deflecting an optical path byreflection, the optical path deflection section being formed on thesurface of the substrate so as to be in a position intersecting theoptical axis of the light receiving/emitting element mounted on thestage portion.

[0024] Thus, according to the third aspect, a stage portion, used forthe positioning of a light receiving/emitting element and an opticalpath deflection section for deflecting light through reflection areconcurrently molded onto an optical package substrate. As a result, apassive alignment of an optical component and an optical element can beeasily realized without requiring any additional processing steps.

[0025] According to a fourth aspect according to the present inventionbased on the third aspect, a waveguide section is further comprisedwhich is formed on the surface of the substrate, the waveguide sectioncorresponding to an optical waveguide core pattern having an opticalaxis coinciding with an optical axis of the light receiving/emittingelement mounted on the stage portion.

[0026] Thus, according to the fourth aspect, a waveguide sectioncorresponding to an optical waveguide core pattern, a stage portion, andan optical path deflection section are concurrently molded onto anoptical package substrate. As a result, a passive alignment of anoptical component and an optical element can be easily realized withoutrequiring any additional processing steps.

[0027] Preferably, a thin film element having a mirror property isprovided on the optical path deflection section. As a result, it becomespossible not only to merely reflect light at the optical path deflectionsection, but also obtain a different reflectance depending on thewavelength of light.

[0028] Alternatively, a diffraction grating for creating differentoptical paths for different optical wavelengths is provided on theoptical path deflection section. As a result, by utilizing theproperties of a diffraction grating having different diffraction anglesfor different wavelengths, an optical device comprising a filteringfunction for receiving light of only a specific wavelength can berealized.

[0029] Alternatively, the optical path deflection section has acurvature for converging a plurality of incident rays throughreflection. As a result, the positioning precision for a light receivingelement can be further relaxed, or light emitted from a surface emissiontype light emitting element can be converged so as to be coupled to anoptical fiber or an optical waveguide with a high efficiency.

[0030] The optical package substrate preferably comprises glass. Byemploying glass, it becomes possible to form highly preciseconfiguration on a surface by means of a die, and excellent stabilitycan be provided in various environments. Since glass is transmissive toUV rays, the fixing of an optical fiber or the like can be achieved byusing a UV-curing adhesive, instead of a time-consuming thermosettingadhesive.

[0031] Furthermore, the optical package substrate may be molded bypressing a die against a substrate material softened by being heated toa high temperature to transcribe an inverted pattern of the die onto thesubstrate material, the die having been obtained by using anormal-grinding tool and an arbitrary fine-grinding tool, wherein atleast one of the die and the fine-grinding tool is obtained throughmicrodischarge machining.

[0032] By producing a die having a complicated configuration throughmicrodischarge machining employing this method for producing an opticalpackage substrate, which would have been highly difficult to obtain by aconventional grinding process, the optical package substrate accordingto the present invention can be obtained.

[0033] A fifth aspect according to the present invention is directed toan optical device having an optical component and/or optical elementmounted on an optical package substrate, the optical package substratecomprising: a guide section for fixing an optical axis of an opticalfiber mounted in the guide section, the guide section being a grooveformed on a surface of a substrate and extending from an end face of thesubstrate to a predetermined portion of the substrate; and an opticalpath deflection section for deflecting an optical path by reflection,the optical path deflection section being formed at the predeterminedportion of the guide section so as to be in a position intersecting theoptical axis of the optical fiber mounted in the guide section, whereinthe optical fiber placed in the guide section on the optical packagesubstrate is pressed from above by a predetermined substrate, wherebythe optical fiber is affixed to the optical package substrate.

[0034] Thus, according to the fifth aspect, an optical fiber can befirmly mounted on an optical package substrate, and an optical devicecapable of deflecting light propagated through an optical fiber can beproduced from the optical package substrate through very simple steps,leading to excellent productivity and economy. It is also possible toemploy a predetermined substrate as a stage on which to mount aphotodiode, a laser, or the like.

[0035] A sixth aspect according to the present invention is directed toan optical device having an optical component and/or optical elementmounted on an optical package substrate, the optical package substratecomprising: a waveguide section as a groove formed on a surface of asubstrate and extending from an end face of the substrate to apredetermined portion of the substrate, the waveguide sectioncorresponding to a predetermined optical waveguide core pattern; and anoptical path deflection section for deflecting an optical path byreflection, the optical path deflection section being formed at thepredetermined portion of the waveguide section so as to be in a positionintersecting an optical axis of the optical waveguide defined in thewaveguide section, the optical device further comprising a predeterminedsubstrate, wherein a core material having a refractive index higher thana refractive index of the optical package substrate is filled in thewaveguide section of the optical package substrate, and thereafter anadhesive having a refractive index lower than the refractive index ofthe core material is used to attach the predetermined substrate to thewaveguide section.

[0036] Thus, according to the sixth aspect, by filling a core materialhaving a high refractive index in a waveguide section so that thewaveguide section functions as an optical waveguide, an optical devicecapable of deflecting light propagated through an optical fiber can beproduced from the optical package substrate through very simple steps,leading to excellent productivity and economy.

[0037] A seventh aspect according to the present invention is directedto an optical device having an optical component and/or optical elementmounted on an optical package substrate, the optical package substratecomprising: a stage portion for fixing an optical axis of a lightreceiving/emitting element mounted on the stage portion, the stageportion being formed on a surface of a substrate; and an optical pathdeflection section for deflecting an optical path by reflection, theoptical path deflection section being formed on the surface of thesubstrate so as to be in a position intersecting the optical axis of thelight receiving/emitting element mounted on the stage portion whereinthe light receiving/emitting element is affixed to the stage portion onthe optical package substrate.

[0038] Thus, according to the seventh aspect, an optical device capableof realizing optical coupling between a light receiving/emitting elementand another optical element can be produced from an optical packagesubstrate through very simple steps, by simply affixing a lightreceiving/emitting element on a stage portion through passive alignment.Thus, excellent productivity and economy can be obtained.

[0039] According to an eighth aspect according to the present inventionbased on the seventh aspect, the optical package substrate furthercomprises a waveguide section formed on the surface of the substrate,the waveguide section corresponding to an optical waveguide core patternhaving an optical axis coinciding with an optical axis of the lightreceiving/emitting element mounted on the stage portion, the opticaldevice further comprising a predetermined substrate, wherein a corematerial having a refractive index higher than a refractive index of theoptical package substrate is filled in the waveguide section of theoptical package substrate, and thereafter an adhesive having arefractive index lower than the refractive index of the core material isused to attach the predetermined substrate to the waveguide section.

[0040] Thus, according to the eighth aspect, an optical device capableof realizing optical coupling between a light receiving/emitting elementand another optical element can be produced from an optical packagesubstrate through very simple steps, by simply affixing a lightreceiving/emitting element on a stage portion through passive alignment.Thus, excellent productivity and economy can be obtained.

[0041] The optical device may further comprise a surface mounting typelight receiving/emitting element which is optically coupled to theoptical fiber affixed in the guide section through the optical pathdeflected by the optical path deflection section. Alternatively, theoptical device may further comprise a surface mounting type lightreceiving/emitting element which is optically coupled to the opticalwaveguide defined in the waveguide section through the optical pathdeflected by the optical path deflection section. Alternatively, theoptical device may further comprise a surface mounting type lightreceiving/emitting element which is optically coupled to the lightreceiving/emitting element affixed to the stage portion through theoptical path deflected by the optical path deflection section. Thus,since the light receiving/emitting element is of a surface mountingtype, the light receiving/emitting element can be mounted even with arelaxed positioning precision. As a result, adjustment-free mounting canbe easily realized.

[0042] These and other objects, features, aspects and advantages of thepresent invention will become more apparent from the following detaileddescription of the present invention when taken in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0043]FIG. 1 is a perspective view illustrating the configuration of anoptical package substrate according to a first embodiment of the presentinvention;

[0044]FIG. 2 is a cross-sectional view illustrating an optical deviceincorporating the optical package substrate according to the firstembodiment;

[0045]FIG. 3 is a perspective view illustrating the configuration of anoptical package substrate according to a second embodiment of thepresent invention;

[0046]FIG. 4 is a cross-sectional view illustrating an optical deviceincorporating the optical package substrate according to the secondembodiment;

[0047]FIG. 5 is a perspective view illustrating the configuration of anoptical package substrate according to a third embodiment of the presentinvention;

[0048]FIG. 6 is a cross-sectional view illustrating an optical deviceincorporating the optical package substrate according to the thirdembodiment;

[0049]FIG. 7 is a perspective view illustrating the configuration of anoptical package substrate according to a fourth embodiment of thepresent invention;

[0050]FIG. 8 includes a perspective view and a cross-sectional viewillustrating an optical device incorporating the optical packagesubstrate according to the fourth embodiment;

[0051]FIG. 9A and FIG. 9B are diagrams illustrating a method for formingan optical waveguide utilizing a waveguide channel on an optical packagesubstrate;

[0052]FIG. 10 is a perspective view illustrating the configuration of anoptical package substrate according to a fifth embodiment of the presentinvention.

[0053]FIG. 11 is a cross-sectional view illustrating an optical deviceincorporating the optical package substrate according to the fifthembodiment;

[0054]FIG. 12 is a perspective view illustrating the configuration of anoptical package substrate according to a sixth embodiment of the presentinvention;

[0055]FIG. 13 includes a perspective view and a cross-sectional viewillustrating an optical device incorporating the optical packagesubstrate according to the sixth embodiment;

[0056]FIG. 14 is a schematic diagram illustrating general principles ofdischarge machining;

[0057]FIG. 15 is a diagram illustrating a method for fine-processing atool electrode through microdischarge machining;

[0058]FIG. 16 is a perspective view illustrating a die used for themolding of the optical package substrate according to the firstembodiment;

[0059]FIG. 17A is a perspective view illustrating exemplary toolelectrodes which are fine-processed through microdischarge machining;

[0060]FIG. 17B and FIG. 17C are diagrams illustrating how a die can bemade by using the tool electrode shown in FIG. 17A;

[0061]FIG. 18A and FIG. 18B are views illustrating a conventionalprocessing method for a die used for the molding a of a generally-used Vgroove; and

[0062]FIG. 19 and FIG. 20 are cross-sectional views illustratingconventional optical devices incorporating optical package substrates.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0063] Hereinafter, illustrative embodiments of the present inventionwill be described with reference to the figures.

[0064] (First Embodiment)

[0065]FIG. 1 is a perspective view illustrating the configuration of anoptical package substrate 11 according to a first embodiment of thepresent invention. As shown in FIG. 1, a guide groove 12 for positioningan optical fiber is formed on the surface of the optical packagesubstrate 11, with a tapered face 13 being formed adjoining the guidegroove 12. The tapered face 13 constitutes a predetermined angle withrespect to the surface of the optical package substrate 11.

[0066]FIG. 2 is a cross-sectional view illustrating an optical deviceincorporating the optical package substrate 11 of FIG. 1, with anoptical fiber 15 and a surface reception type photodiode 16 beingmounted thereon.

[0067] As shown in FIG. 2, the optical device structure incorporatingthe optical package substrate 11 includes a mirror 17 composed of a thinfilm capable of reflecting light, which is formed on the tapered face13. The optical fiber 15 is affixed in the guide groove 12 by using anultraviolet (UV)-curing resin, for example. The optical fiber 15 onlyneeds to be placed within the guide groove 12, but is preferably placedin such a manner that an end face thereof abuts against the tapered face13, as shown in FIG. 2. Above the tapered face 13 is mounted the surfacereception type photodiode 16, which is placed in a position forreceiving light deflected by the mirror 17 provided on the tapered face13. By providing a positioning marker (not shown) for a light receivingelement on the optical package substrate 11, it becomes particularlyeasy to mount the surface reception type photodiode 16 through passivealignment.

[0068] In accordance with this structure, light which is propagatedthrough the optical fiber 15 in the left to right direction in FIG. 2exits the optical fiber 15 at its right end face, and thereafter isreflected from the mirror 17 provided on the tapered face 13, so as toenter the surface reception type photodiode 16 (see the arrow in FIG.2). Thus, the optical device shown in FIG. 2 incorporating the opticalpackage substrate 11 functions as a light receiving module.

[0069] As described above, by employing the optical package substrate 11according to the first embodiment of the present invention, it ispossible to produce an optical device capable of easily deflecting thelight which exits the optical fiber 15. Moreover, there is no need towatch the rotation of the optical fiber 15 during the mounting of acomponent.

[0070] The mirror 17 on the tapered face 13 may be formed by directlyapplying a metal film through a plating or vacuum process.Alternatively, a mirror which is previously formed on another substratemay be attached by adhering the substrate onto the tapered face 13.Instead of a mirror, a multilayer film filter which reflects light of atarget optical wavelength may be formed on the tapered face 13.

[0071] In practice, the aforementioned angle of the tapered face 13 ispreferably in the range of about 30° to about 70°. In particular, in thecase where a multilayer film filter is formed on the tapered face 13, itis preferable that the angle is about 60° or more as to minimize anyfluctuations in characteristics associated with polarization.

[0072] Furthermore, the cross section of the guide groove 12 is notlimited to a V shape. Rather, any cross sectional shape may be usedwhich permits the optical fiber 15 to be positioned therein, e.g.,rectangular, semicircular, or like shapes.

[0073] Instead of the aforementioned optical fiber 15, an optical fiber191 shown in FIG. 19 may be employed, which is provided with a mirrorthat is ground at a predetermined angle on one end face; in this case,it is unnecessary to form the mirror 17 on the tapered face 13. Evenwhen such an optical fiber 191 is employed, the tapered face 13 formedon the optical package substrate 11 prevents the rotation of the opticalfiber 191 during the mounting of a component.

[0074] (Second Embodiment)

[0075]FIG. 3 is a perspective view illustrating the configuration of anoptical package substrate 31 according to a second embodiment of thepresent invention. As shown in FIG. 3, a guide groove 32 for positioningan optical fiber is formed on the surface of the optical packagesubstrate 31, with a tapered face 33 being formed adjoining the guidegroove 32. The tapered face 33 constitutes a predetermined angle withrespect to the surface of the optical package substrate 31. The surfaceof the package substrate 31 is staggered at the slope 34.

[0076]FIG. 4 is a cross-sectional view illustrating an optical deviceincorporating the optical package substrate 31 shown in FIG. 3, on whichan optical fiber 35 and a surface reception type photodiode 36 aremounted.

[0077] In the optical device structure shown in FIG. 4 incorporating theoptical package substrate 31, a diffraction grating 37 for causingoptical diffraction is provided on the tapered face 33. The opticalfiber 35 is affixed in the guide groove 32. The optical fiber 35 onlyneeds to be placed within the guide groove 32, but is preferably placedin such a manner that an end face thereof abuts against the tapered face33, as shown in FIG. 4. The optical fiber 35 is pressed in place bymeans of a flat glass plate 38, which in itself is placed so as to abutagainst the slope 34. Above the flat glass plate 38 is mounted apatterned absorption film 39 having an aperture. The surface receptiontype photodiode 36 is mounted in a face-down manner, with a sensorportion thereof being aligned with the aperture in the absorption film39. By providing a positioning marker (not shown) for a light receivingelement on the absorption film 39, it becomes particularly easy to mountthe surface reception type photodiode 36 through passive alignment. Theoptical fiber 35 and the flat glass plate 38 may be fixed by usingUV-curing resin, for example.

[0078] In accordance with this structure, light which is propagatedthrough the optical fiber 35 in the left to right direction in FIG. 4exits the optical fiber 35 at its right end face, and thereafter isdiffracted by the diffraction grating 37 provided on the tapered face33. The diffraction grating 37 functions to provide differentdiffraction angles depending on the wavelength of light. Therefore, byinserting the absorption film 39 between the diffraction grating 37 andthe surface reception type photodiode 36, it becomes possible to ensurethat light of only a specific wavelength is received at the surfacereception type photodiode 36 (see the arrows in FIG. 4). Thus, theoptical device shown in FIG. 4 incorporating the optical packagesubstrate 31 functions as a light receiving module having a wavelengthselecting function.

[0079] As described above, by employing the optical package substrate 31according to the second embodiment of the present invention, it ispossible to produce an optical device capable of easily deflecting thelight which exits the optical fiber 35 and capable of wavelengthselection. Moreover, there is no need to watch the rotation of theoptical fiber 35 during the mounting of a component.

[0080] The diffraction grating 37 on the tapered face 33 may be formedby directly processing the tapered face 33. Alternatively, a diffractiongrating which is previously formed on another substrate may be attachedby adhering the substrate onto the tapered face 33. It is particularlypreferable to form an inverted pattern of a desired diffraction gratingon a tapered face of a die for use in the molding of the optical packagesubstrate, and then perform a press formation of the optical packagesubstrate in such a manner that the diffraction grating 37 is moldedconcurrently with other portions.

[0081] In practice, the aforementioned angle of the tapered face 33 ispreferably in the range of about 30° to about 70°.

[0082] In order to enhance the accuracy of wavelength separation, theaperture of the absorption film 39 may be made narrower, or thethickness of the flat glass plate 38 may be increased.

[0083] Furthermore, the cross section of the guide groove 32 is notlimited to a V shape. Rather, any cross sectional shape may be usedwhich permits the optical fiber 35 to be positioned therein, e.g.,rectangular, semicircular, or like shapes.

[0084] (Third Embodiment)

[0085]FIG. 5 is a perspective view illustrating the configuration of anoptical package substrate 51 according to a third embodiment of thepresent invention. As shown in FIG. 5, a guide groove 52 for positioningan optical fiber is formed on the surface of the optical packagesubstrate 51, with a predetermined tapered face 53 being formedadjoining the guide groove 52.

[0086]FIG. 6 is a cross-sectional view illustrating an optical deviceincorporating the optical package substrate 51 shown in FIG. 5, on whichan optical fiber 55 and a surface emission type laser 56 are mounted.

[0087] As shown in FIG. 6, the optical device structure incorporatingthe optical package substrate 51 includes a tapered face 53 having alens-like curvature, with a mirror 57 composed of a thin film capable ofreflecting light formed on the surface of the tapered face 53. Theoptical fiber 55 is affixed in the guide groove 52. The optical fiber 55only needs to be placed within the guide groove 52, but is preferablyplaced in such a manner that an end face thereof abuts against thetapered face 53, as shown in FIG. 6. The optical fiber 55 is pressed inplace by means of a flat glass plate 58. The flat glass plate 58 ispositioned by using a marker (not shown) previously provided on theoptical package substrate 51. Above the flat glass plate 58 is mountedthe surface emission type laser 56, which is placed in a position forreceiving light deflected by the mirror 57 provided on the tapered face53. By providing a positioning marker (not shown) for a light emittingelement on the flat glass plate 58, it becomes easy to mount the surfaceemission type laser 56 through passive alignment. In other words, byperforming the alignment between the flat glass plate 58 and the opticalpackage substrate 51 and the alignment between the flat glass plate 58and the surface emission type laser 56 each based on a marker, itbecomes possible to align the surface emission type laser 56 withrespect to the optical package substrate 51. The optical fiber 55 andthe flat glass plate 58 may be fixed by using UV-curing resin, forexample.

[0088] In accordance with this structure, light exiting the surfaceemission type laser 56 arrives at the tapered face 53 as it spreads out.The arriving light is reflected and converged by the mirror 57 providedon the tapered face 53, so as to be coupled to the optical fiber 55 (seethe arrows in FIG. 6). Thus, the optical device shown in FIG. 6incorporating the optical package substrate 51 functions as a lighttransmitting module.

[0089] By replacing the surface emission type laser 56 with a surfacereception type photodiode, the optical device can function as a lightreceiving module for causing light exiting the optical fiber 55 to bereflected and converged by the mirror 57 so as to enter the surfacereception type photodiode.

[0090] As described above, by employing the optical package substrate 51according to the third embodiment of the present invention, it ispossible to produce an optical device capable of easily deflecting thelight which exits the surface emission type laser 56 so as to be coupledto the optical fiber 55. Moreover, there is no need to watch therotation of the optical fiber 55 during the mounting of a component.

[0091] The mirror 57 on the tapered face 53 may be formed by directlyapplying a metal film through a plating or vacuum process.Alternatively, a mirror which is previously formed on another substratemay be attached by adhering the substrate onto the tapered face 53.Instead of a mirror, a multilayer film filter which reflects light of atarget optical wavelength may be formed on the tapered face 53.

[0092] Furthermore, the cross section of the guide groove 52 is notlimited to a V shape. Rather, any cross sectional shape may be usedwhich permits the optical fiber 55 to be positioned therein, e.g.,rectangular, semicircular, or like shapes.

[0093] (Fourth Embodiment)

[0094] The above-described first to third embodiments each illustrate anoptical package substrate comprising a guide groove for fixing anoptical fiber. In each of the following embodiments, an optical packagesubstrate and an optical device are illustrated which are provided witha waveguide channel corresponding to an optical waveguide core patternthat functions to contain light within the core and allows it to bepropagated therethrough in the manner of an optical fiber.

[0095]FIG. 7 is a perspective view illustrating the configuration of anoptical package substrate 71 according to a fourth embodiment of thepresent invention. As shown in FIG. 7, a waveguide channel 72corresponding to an optical waveguide core pattern is formed on thesurface of the optical package substrate 71, with a tapered face 73being formed adjoining the waveguide channel 72. The tapered face 73constitutes a predetermined angle with respect to the surface of theoptical package substrate 71. The surface of the optical packagesubstrate 71 is staggered so as to result in a predetermined leveldifference between a plane on which the waveguide channel 72 is formedand another plane.

[0096]FIG. 8 includes a perspective view and a cross-sectional viewillustrating an optical device incorporating the optical packagesubstrate 71 shown in FIG. 7, on which a surface reception typephotodiode 76 is mounted.

[0097] Now, a method for forming an optical waveguide in the waveguidechannel 72 will be described with reference to FIG. 9. FIG. 9 shows across-sectional view of an optical waveguide formed in the opticalpackage substrate 71.

[0098] First, a transparent base material 91 with a UV-curing adhesive92 being thinly applied thereon is prepared. The transparent basematerial 91 has a refractive index similar to that of the opticalpackage substrate 71 in which the waveguide channel 72 is formed,whereas the UV-curing adhesive 92 has a refractive index higher thanthose of the optical package substrate 71 and the transparent basematerial 91 (FIG. 9A). Then, the transparent base material 91 isattached to the optical package substrate 71 in such a manner that theface on which the UV-curing adhesive 92 is applied faces the waveguidechannel 72 (FIG. 9B). Finally, the transparent base material 91 and theoptical package substrate 71 are irradiated with UV rays so that theyadhere to each other. According to this formation method, by ensuringthat the layer of adhesive which is present in portions other than thewaveguide channel 72 created as a result of the above attachment issufficiently thin, the UV-curing adhesive 92 embedded within thewaveguide channel 72 can be allowed to function as an optical waveguide.

[0099] In the optical device structure incorporating the optical packagesubstrate 71 illustrated in FIG. 8, the flat glass plate 78 is attachedto the optical package substrate 71 via a UV-curing adhesive so as tooverlie the waveguide channel 72, where the UV-curing adhesive isselected to have a higher refractive index than those of the opticalpackage substrate 71 and the flat glass plate 78, as described above. Asa result, the waveguide channel 72 functions as an optical waveguide.The thickness of the flat glass plate 78 is preferably set so that itsupper face (as attached to the optical package substrate 71) lies flushwith the other plane of the optical package substrate 71. A mirror 77composed of a thin film capable of reflecting light is formed on thetapered face 73. Above the optical package substrate 71 and the flatglass plate 78 is formed the surface reception type photodiode 76, whichis placed in a position for receiving light deflected by the mirror 77provided on the tapered face 73. By providing a positioning marker (notshown) for a light receiving element on the optical package substrate 71or the flat glass plate 78, it becomes particularly easy to mount thesurface reception type photodiode 76 through passive alignment.

[0100] In accordance with this structure, light which is propagatedthrough the optical waveguide defined in the waveguide channel 72 in theleft to right direction in FIG. 8 exits the optical waveguide at itsright end face, and thereafter is reflected from the mirror 77 providedon the tapered face 73, so as to enter the surface reception typephotodiode 76 (see the arrow in FIG. 8). Thus, the optical device shownin FIG. 8 incorporating the optical package substrate 71 functions as alight receiving module.

[0101] As described above, by employing the optical package substrate 71according to the fourth embodiment of the present invention, an opticalwaveguide can be easily formed, and it is possible to produce an opticaldevice capable of easily deflecting the light which exits the opticalwaveguide.

[0102] (Fifth Embodiment)

[0103]FIG. 10 is a perspective view illustrating the configuration of anoptical package substrate 101 according to a fifth embodiment of thepresent invention. As shown in FIG. 10, a stage 109 for positioning alaser is formed on the surface of the optical package substrate 101,with a tapered face 103 being formed. The tapered face 103 constitutes apredetermined angle with respect to the surface of the optical packagesubstrate 101. The surface of the optical package substrate 101 isstaggered so as to result in a predetermined level difference between aplane on which the stage 109 is formed and another plane.

[0104]FIG. 11 includes a perspective view and a cross-sectional viewillustrating an optical device incorporating the optical packagesubstrate 101 shown in FIG. 10, on which a waveguide type laser 110 anda surface reception type photodiode 106 are mounted.

[0105] As shown in FIG. 11, the optical device structure incorporatingthe optical package substrate 101 includes a mirror 107 composed of athin film capable of reflecting light, which is formed on the taperedface 103. The waveguide type laser 110 is mounted on the stage 109through passive alignment, with reference to a positioning marker (notshown) provided on the stage 109. The plane of the optical packagesubstrate 101 on which the stage 109 is formed is configured so thatlight exiting the waveguide type laser 110 placed thereon is incident onthe tapered face 103. The surface reception type photodiode 106 is alsomounted through passive alignment, with reference to a positioningmarker (not shown) provided on the optical package substrate 101, so asto be placed in a position for receiving light deflected by the mirror107 provided on the tapered face 103.

[0106] In accordance with this structure, principal light which isemitted from the waveguide type laser 110 in the left direction in FIG.11 is coupled to an optical fiber (not shown) via a lens or the like,whereas subordinate light which is emitted in the right direction inFIG. 11 is reflected from the mirror 107 provided on the tapered face103, so as to enter the surface reception type photodiode 106 (see thearrows in FIG. 11). Thus, the optical device shown in FIG. 11incorporating the optical package substrate 101 functions as a lighttransmitting module which permits the optical output from the waveguidetype laser 110 to be monitored.

[0107] As described above, by employing the optical package substrate101 according to the fifth embodiment of the present invention, it ispossible to produce an optical device capable of easily deflecting thelight which is emitted from the waveguide type laser 110 and permittingthe intensity of the laser light to be monitored.

[0108] (Sixth Embodiment)

[0109]FIG. 12 is a perspective view illustrating the configuration of anoptical package substrate 121 according to a sixth embodiment of thepresent invention. As shown in FIG. 12, a waveguide channel 122corresponding to an optical waveguide core pattern and a stage 129 forpositioning a laser are formed on the surface of the optical packagesubstrate 121, with a tapered face 123 also being formed. The taperedface 123 constitutes a predetermined angle with respect to the surfaceof the optical package substrate 121. The surface of the optical packagesubstrate 121 is staggered so as to result in predetermined leveldifferences between a plane on which waveguide channel 122 is formed, aplane on which the stage 129 is formed, and another plane.

[0110]FIG. 13 includes a perspective view and a cross-sectional viewillustrating an optical device incorporating the optical packagesubstrate 121 shown in FIG. 12, on which a waveguide type laser 130 anda surface reception type photodiode 126 are mounted.

[0111] In the optical device structure incorporating the optical packagesubstrate 121 illustrated in FIG. 13, the flat glass plate 128 isattached to the optical package substrate 121 via a UV-curing adhesiveso as to overlie the waveguide channel 122, where the UV-curing adhesiveis selected to have a higher refractive index than those of the opticalpackage substrate 121 and the flat glass plate 128, as in the fourthembodiment. As a result, the waveguide channel 122 functions as anoptical waveguide. The waveguide type laser 130 is mounted on the stage129 through passive alignment, with reference to a positioning marker(not shown) provided on the stage 129. The plane of the optical packagesubstrate 121 on which the stage 129 is formed is configured so that theoptical axis of principal light which is emitted from the waveguide typelaser 130 placed thereon coincides with the optical axis of the opticalwaveguide defined in the waveguide channel 122, and that the opticalaxis of subordinate light is incident on the tapered face 123. A mirror127 composed of a thin film capable of reflecting light is formed on thetapered face 123. The surface reception type photodiode 126 is mountedthrough passive alignment, with reference to a positioning marker (notshown) provided on the optical package substrate 121, so as to be placedin a position for receiving light deflected by the mirror 127 providedon the tapered face 123.

[0112] In accordance with this structure, principal light which isemitted from the waveguide type laser 130 in the left direction in FIG.13 is coupled to the optical waveguide defined in the waveguide channel122, whereas subordinate light which is emitted in the right directionin FIG. 13 is reflected from the mirror 127 provided on the tapered face123, so as to enter the surface reception type photodiode 126 (see thearrows in FIG. 13). Thus, the optical device shown in FIG. 13incorporating the optical package substrate 121 functions as a lighttransmitting module which combines the functions of the optical devicesaccording to the fourth and fifth embodiments.

[0113] As described above, by employing the optical package substrate121 according to the sixth embodiment of the present invention, anoptical waveguide can be easily formed, and it is possible to produce anoptical device capable of coupling principal light emitted from thewaveguide type laser 130 to the optical waveguide, easily deflecting thesubordinate light, and permitting the intensity of the laser light to bemonitored.

[0114] In each the fourth to sixth embodiments, the mirror 77,107, or127 provided on the tapered face 73,103, or 123 may be formed bydirectly applying a metal film through a plating or vacuum process.Alternatively, a mirror which is previously formed on another substratemay be attached by adhering the substrate onto the tapered face. Insteadof a mirror, a multilayer film filter which reflects light of a targetoptical wavelength may be formed on the tapered face.

[0115] In practice, the aforementioned angle of the tapered face 73,103, or 123 is preferably in the range of about 30° to about 70°. Inparticular, in the case where a multilayer film filter is formed on thetapered face, it is preferable that the angle is about 60° or more as tominimize any fluctuations in characteristics associated withpolarization. The tapered face may alternatively be a curved surface.

[0116] (Optical Package Substrate Molding Method)

[0117] Lastly, a preferable method for molding the optical packagesubstrates according to the first to sixth embodiments will bedescribed. According to the present method, a die for use in the moldingof an optical package substrate is produced, and this resultant die ispressed against a glass material which has been softened by being heatedto a high temperature so as to transcribe the configuration of the dieto the glass material (press formation), whereby the optical packagesubstrate is molded. Although glass material which is thermally,mechanically, and chemically stable is preferable as the material of theoptical package substrate, any other material which permits pressformation can also be used. The inventors have confirmed throughexperimentation that press formation can be successfully performed bypressing an ultra-hard alloy die, on which a protective film composed ofa precious metal alloy is formed, against an optical glass substratewhich is heated to 580° C. in a nitrogen gas atmosphere.

[0118] Hereinafter, a processing method for a die, which constitutes anessential portion in the production of an optical package substrate,specifically a die processing method utilizing microdischarge machining,will be described. For details of microdischarge machining, see TheJournal of the Japan Society for Precision Engineering, vol.61, No.10,p. 1370 (1995), or Optical Alliance, 1995.3, p. 28.

[0119]FIG. 14 is a schematic diagram illustrating general principles ofdischarge machining. Referring to FIG. 14, a tool electrode 142 attachedat the tip of a mandrel 141, which defines a rotation axis, and a work143 (which functions as an electrode) as an object to be processed areimmersed in an insulation liquid 144. In this commonly-practiceddischarge machining, the two electrodes are brought close to each otherwhile applying a predetermined voltage between the tool electrode 142and the work 143 by means of a discharge generation section 145, therebycausing an electrical discharge through which the work 143 is meltedaway. As a wider gap is created due to the melting of the work 143, thetool electrode 142 is further advanced by a corresponding distance. Thisprocess is repeated in order to process the work 143 into a desiredconfiguration.

[0120] A microdischarge machining technique, which is based on similarprocessing principles, utilizes a special discharge circuit to provide adischarge energy which is about {fraction (1/100)} of what is normallyused, thereby realizing coarse processing on the order of microns andfine processing on the order of sub-microns. This microdischargemachining technique mainly has the following features:

[0121] (1) curved surfaces can be processed since the technique is basedon non-contact processing;

[0122] (2) any electrically conductive material can be processed,regardless of its mechanical hardness;

[0123] (3) microprocessing (on the order of 0.1 μm) is enabled; and

[0124] (4) microconfigurations can be processed since tools having adiameter of several microns can be used.

[0125] In the molding of the optical package substrate according to eachembodiment of the present invention, it is important to utilizemicrodischarge machining to process the configuration of not only thework but also the tool electrode itself, by taking advantage of the fineprocessing ability of microdischarge machining technique. As a result, atool electrode of any configuration (e.g., triangular prism or arectangular prism as well as a cylinder) can be realized in units ofseveral millimeters or more. For example, since the tip of a toolelectrode composed of sintered diamond or the like can be fine-processedinto a cylindrical or conical shape, such a tool electrode can be usedfor microgrinding a die.

[0126] Now, a method for fine processing a tool electrode will bedescribed with reference to FIG. 15. A processing method which can beadopted in the fine processing of a tool electrode is in itselfdisclosed in Japanese Patent Laid-Open Publication No. 2001-54808.

[0127] Referring to FIG. 15, a shaft-like tool material 152, which is tobe processed, is attached to the tip of the mandrel 151. The position ofthe tool material 152 can be moved up or down along the rotation axisdirection by means of a Z stage 157 equipped with a motor 156. Within aprocessing bath 159 which is placed on an X-Y stage 158, an electrodeplate 153 for discharge machining is fixed. In the example illustratedin FIG. 15, the electrode plate 153 for discharge machining is fixed soas to be parallel to the Y axis and at an angle of 45° to the X-Y plane.The inside of the processing bath 159 is filled with an insulationliquid 154. A discharge generation section 155 composed of an RC circuitcapable of generating discharge pulses of a minute energy level iscoupled between the tool material 152 and the electrode plate 153 fordischarge machining. Thus, it is possible to perform a microdischargemachining on the order of μm for the tool material 152.

[0128] In accordance with the above system configuration, the tip of thetool material 152 can be processed into a desired configuration throughmicrodischarge machining while sending the tool material 152, which isrotated (or reciprocated), toward the electrode plate 153 for dischargemachining by means of the Z stage 157. FIG. 15 illustrates an examplewhere the tool material 152 is processed so as to have a conical tipwhile being rotated. Note that sintered diamond for which a metal hasbeen used as a binder can be employed as the tool material 152 becausesuch sintered diamond is electrically conductive.

[0129] In order to attain efficiency in die production, the followingwork will ensue the processing of the tool material 152.

[0130] By employing the X-Y stage 158 and the Z stage 157, the processedtool material 152, i.e., the tool electrode, is moved toward the work160 which has previously been fixed in the processing bath 159, andpositioned in place. This positioning can be achieved by detectingelectrical conduction between the tool electrode and the work 160 andthe two are gradually brought near. Next, the tool electrode and ismoved in a desired direction while being rotated, so as to be pressedagainst a portion previously processed on the surface of the work 160which requires precision finishing (i.e., the slopes of a V-shapedprotrusion in the example shown in FIG. 15). As a result, the shapingprecision and planar precision of the desired portion (i.e., the slopesof the V-shaped protrusion in this example) can be improved.

[0131] For example, a die to be used for the molding of the opticalpackage substrate 11 according to the first embodiment would have aconfiguration as shown in FIG. 16, such that a protrusion 161 formolding the guide groove 12 is provided on the surface thereof. In orderto form such a protrusion 161 having the shape of a triangular prism onthe die, a tool electrode 171 having the shape of a triangular prism anda scalpel-shaped tool electrode 172 as shown in FIG. 17A are firstproduced. Then, a microdischarge machining process is first performed byusing the tool electrode 171 while maintaining the work 173 in anupright position (as shown in the left-hand side of FIG. 17B), and atriangular-prism-like protrusion is coarsely processed on the surface ofthe work 173 (as shown in the right-hand-side of FIG. 17). Then, whilemaintaining the work 173 in a lying position, a grinding process isperformed by using the tool electrode 172 (as shown in the left-handside of FIG. 17C), and the protrusion 161 which has been formed on thework 173 is fine-processed (as shown in the right-hand side of FIG.17C).

[0132] Thus, by employing a method which makes use of a fine-processedtool electrode, it becomes possible to realize an ultra-hard alloy diehaving a sub-micron level shaping precision, which is mirror-finished toa surface coarseness on the order of Ra 20 nm or less, although this hasconventional been impossible. As the planar precision of the die surfaceimproves, the positioning precision of optical fibers or othercomponents (e.g., the planar precision of the guide groove) is improved,whereby the performance of the optical coupling efficiency can beimproved. Moreover, since an improved planar precision of the diesurface facilitates the release process which is associated withmolding, the die is exposed to less stress, whereby the durability ofthe die is improved for a higher productivity and economy.

[0133] Note that a conventional microgrinder-based grinding process willresult in a surface coarseness several times the aforementioned value.This is presumably because a grinding process which utilizes amicrogrinder naturally requires a continuous and high-speed processingdown to a substantial depth, resulting in a lower planar precision ofthe final plane.

[0134] For comparison, a conventional die processing method for moldinga general V groove which utilizes a microgrinder will be described withreference to FIGS. 18A and 18B.

[0135] A circular diamond grindstone 181 having a V-shaped edge isemployed as a grindstone for a microgrinder. As shown in FIG. 18A, byperforming grinding process with a this grindstone 181 from an end of aplane-like ultra-hard alloy 182, a die 183 as shown in FIG. 18B can beobtained.

[0136] However, there is a limit to the planar precision which can beobtained through microgrinder processing. For example, in the case ofthe die for use with an optical package substrate 11 as shown in FIG.16, the portion of the protrusion 161 corresponding to the tapered face13 cannot be processed so as to have a sufficient reflectance. In otherwords, it would be highly difficult to process a complicatedconfiguration with a microgrinder, and only dies with relatively simpleconfigurations can be produced through microgrinder processing.

[0137] As described above, by utilizing microdischarge machining for theprocessing of a tool electrode, it becomes possible to produce of highlyprecise tool electrodes of various configurations, which in turn allowfor the production of dies having complicated configurations. Therefore,through press formation using such dies, optical package substrates canbe produced in large quantities and at low cost. Thus, it becomespossible to mount an optical fiber, optical waveguide, a lightreceiving/emitting element, or the like on an optical package substratewithout the need for adjustment, so that optical devices (or opticaltransmission/reception modules) incorporating such elements can also beproduced in large quantities and at low cost.

[0138] Although an ultra-hard alloy is exemplified as a die material inthe above description, any electrically conductive material having asufficient heat resistance and mechanical strength can be used, e.g.,SUS. Alternatively, an ultra-hard alloy or the like may be used as aparent material for a die; an electrically conductive film such as aprecious metal alloy film may be formed on the surface there of; andthis film may be processed into a desired configuration.

[0139] While the invention has been described in detail, the foregoingdescription is in all aspects illustrative and not restrictive. It isunderstood that numerous other modifications and variations can bedevised without departing from the scope of the invention.

What is claimed is:
 1. An optical package substrate for mounting anoptical component and/or an optical element thereon, comprising: a guidesection for fixing an optical axis of an optical fiber mounted in theguide section, the guide section being a groove formed on a surface of asubstrate and extending from an end face of the substrate to apredetermined portion of the substrate; and an optical path deflectionsection for deflecting an optical path by reflection, the optical pathdeflection section being formed at the predetermined portion of theguide section so as to be in a position intersecting the optical axis ofthe optical fiber mounted in the guide section.
 2. The optical packagesubstrate according to claim 1, wherein a thin film element having amirror property is provided on the optical path deflection section. 3.The optical package substrate according to claim 1, wherein adiffraction grating for creating different optical paths for differentoptical wavelengths is provided on the optical path deflection section.4. The optical package substrate according to claim 1, wherein theoptical path deflection section has a curvature for converging aplurality of incident rays through reflection.
 5. The optical packagesubstrate according to claim 1, wherein the optical package substratecomprises glass.
 6. The optical package substrate according to claim 1,wherein the optical package substrate is molded by pressing a dieagainst a substrate material softened by being heated to a hightemperature to transcribe an inverted pattern of the die onto thesubstrate material, the die having been obtained by using anormal-grinding tool and an arbitrary fine-grinding tool, wherein atleast one of the die and the fine-grinding tool is obtained throughmicrodischarge machining.
 7. The optical package substrate according toclaim 5, wherein the optical package substrate is molded by pressing adie against a substrate material softened by being heated to a hightemperature to transcribe an inverted pattern of the die onto thesubstrate material, the die having been obtained through microdischargemachining using a normal-grinding tool and an arbitrary fine-grindingtool which in itself is produced through microdischarge machining.
 8. Anoptical package substrate for mounting an optical component and/or anoptical element thereon, comprising: a waveguide section as a grooveformed on a surface of a substrate and extending from an end face of thesubstrate to a predetermined portion of the substrate, the waveguidesection corresponding to a predetermined optical waveguide core pattern;and an optical path deflection section for deflecting an optical path byreflection, the optical path deflection section being formed at thepredetermined portion of the waveguide section (72) so as to be in aposition intersecting an optical axis of the optical waveguide definedin the waveguide section.
 9. The optical package substrate according toclaim 8, wherein a thin film element having a mirror property isprovided on the optical path deflection section.
 10. The optical packagesubstrate according to claim 8, wherein a diffraction grating forcreating different optical paths for different optical wavelengths isprovided on the optical path deflection section.
 11. The optical packagesubstrate according to claim 8, wherein the optical path deflectionsection has a curvature for converging a plurality of incident raysthrough reflection.
 12. The optical package substrate according to claim8, wherein the optical package substrate comprises glass.
 13. Theoptical package substrate according to claim 8, wherein the opticalpackage substrate is molded by pressing a die against a substratematerial softened by being heated to a high temperature to transcribe aninverted pattern of the die onto the substrate material, the die havingbeen obtained through microdischarge machining using a normal grindingtool and an arbitrary fine-grinding tool which in itself is producedthrough microdischarge machining.
 14. The optical package substrateaccording to claim 12, wherein the optical package substrate is moldedby pressing a die against a substrate material softened by being heatedto a high temperature to transcribe an inverted pattern of the die ontothe substrate material, the die having been obtained throughmicrodischarge machining using a normal grinding tool and an arbitraryfine-grinding tool which in itself is produced through microdischargemachining.
 15. An optical package substrate for mounting an opticalcomponent and/or an optical element thereon, comprising: a stage portionfor fixing an optical axis of a light receiving/emitting element mountedon the stage portion, the stage portion being formed on a surface of asubstrate; and an optical path deflection section for deflecting anoptical path by reflection, the optical path deflection section beingformed on the surface of the substrate so as to be in a positionintersecting the optical axis of the light receiving/emitting elementmounted on the stage portion.
 16. The optical package substrateaccording to claim 15, wherein a thin film element having a mirrorproperty is provided on the optical path deflection section.
 17. Theoptical package substrate according to claim 15, wherein a diffractiongrating for creating different optical paths for different opticalwavelengths is provided on the optical path deflection section.
 18. Theoptical package substrate according to claim 15, wherein the opticalpath deflection section has a curvature for converging a plurality ofincident rays through reflection.
 19. The optical package substrateaccording to claim 15, wherein the optical package substrate comprisesglass.
 20. The optical package substrate according to claim 15, whereinthe optical package substrate is molded by pressing a die against asubstrate material softened by being heated to a high temperature totranscribe an inverted pattern of the die onto the substrate material,the die having been obtained through microdischarge machining using anormal-grinding tool and an arbitrary fine-grinding tool which in itselfis produced through microdischarge machining.
 21. The optical packagesubstrate according to claim 19, wherein the optical package substrateis molded by pressing a die against a substrate material softened bybeing heated to a high temperature to transcribe an inverted pattern ofthe die onto the substrate material, the die having been obtainedthrough microdischarge machining using a normal grinding tool and anarbitrary fine-grinding tool which in itself is produced throughmicrodischarge machining.
 22. The optical package substrate according toclaim 15, further comprising a waveguide section formed on the surfaceof the substrate, the waveguide section corresponding to an opticalwaveguide core pattern having an optical axis coinciding with an opticalaxis of the light receiving/emitting element mounted on the stageportion.
 23. The optical package substrate according to claim 22,wherein a thin film element having a mirror property is provided on theoptical path deflection section.
 24. The optical package substrateaccording to claim 22, wherein a diffraction grating for creatingdifferent optical paths for different optical wavelengths is provided onthe optical path deflection section.
 25. The optical package substrateaccording to claim 22, wherein the optical path deflection section has acurvature for converging a plurality of incident rays throughreflection.
 26. The optical package substrate according to claim 22,wherein the optical package substrate comprises glass.
 27. The opticalpackage substrate according to claim 22, wherein the optical packagesubstrate is molded by pressing a die against a substrate materialsoftened by being heated to a high temperature to transcribe an invertedpattern of the die onto the substrate material, the die having beenobtained through microdischarge machining using a normal-grinding tooland an arbitrary fine-grinding tool which in itself is produced throughmicrodischarge machining.
 28. The optical package substrate according toclaim 26, wherein the optical package substrate is molded by pressing adie against a substrate material softened by being heated to a hightemperature to transcribe an inverted pattern of the die onto thesubstrate material, the die having been obtained through microdischargemachining using a normal-grinding tool and an arbitrary fine-grindingtool which in itself is produced through microdischarge machining. 29.An optical device having an optical component and/or optical elementmounted on an optical package substrate, the optical package substratecomprising: a guide section for fixing an optical axis of an opticalfiber mounted in the guide section, the guide section being a grooveformed on a surface of a substrate and extending from an end face of thesubstrate to a predetermined portion of the substrate; and an opticalpath deflection section for deflecting an optical path by reflection,the optical path deflection section being formed at the predeterminedportion of the guide section so as to be in a position intersecting theoptical axis of the optical fiber mounted in the guide section, whereinthe optical fiber placed in the guide section on the optical packagesubstrate is pressed from above by a predetermined substrate, wherebythe optical fiber is affixed to the optical package substrate.
 30. Theoptical device according to claim 29, further comprising a surfacemounting type light receiving/emitting element which is opticallycoupled to the optical fiber affixed in the guide section through theoptical path deflected by the optical path deflection section.
 31. Anoptical device having an optical component and/or optical elementmounted on an optical package substrate, the optical package substratecomprising: a waveguide section as a groove formed on a surface of asubstrate and extending from an end face of the substrate to apredetermined portion of the substrate, the waveguide sectioncorresponding to a predetermined optical waveguide core pattern; and anoptical path deflection section for deflecting an optical path byreflection, the optical path deflection section being formed at thepredetermined portion of the waveguide section so as to be in a positionintersecting an optical axis of the optical waveguide defined in thewaveguide section, the optical device further comprising a predeterminedsubstrate, wherein a core material having a refractive index higher thana refractive index of the optical package substrate is filled in thewaveguide section of the optical package substrate, and thereafter anadhesive having a refractive index lower than the refractive index ofthe core material is used to attach the predetermined substrate to thewaveguide section.
 32. The optical device according to claim 31, furthercomprising a surface mounting type light receiving/emitting elementwhich is optically coupled to the optical waveguide defined in thewaveguide section through the optical path deflected by the optical pathdeflection section.
 33. An optical device having an optical componentand/or optical element mounted on an optical package substrate, theoptical package substrate comprising: a stage portion for fixing anoptical axis of a light receiving/emitting element mounted on the stageportion, the stage portion being formed on a surface of a substrate; andan optical path deflection section for deflecting an optical path byreflection, the optical path deflection section being formed on thesurface of the substrate so as to be in a position intersecting theoptical axis of the light receiving/emitting element mounted on thestage portion wherein the light receiving/emitting element is affixed tothe stage portion on the optical package substrate.
 34. The opticaldevice according to claim 33, further comprising a surface mounting typelight receiving/emitting element which is optically coupled to the lightreceiving/emitting element affixed to the stage portion through theoptical path deflected by the optical path deflection section.
 35. Theoptical device according to claim 33, wherein the optical packagesubstrate further comprises a waveguide section formed on the surface ofthe substrate, the waveguide section corresponding to an opticalwaveguide core pattern having an optical axis coinciding with an opticalaxis of the light receiving/emitting element mounted on the stageportion, the optical device further comprising a predeterminedsubstrate, wherein a core material having a refractive index higher thana refractive index of the optical package substrate is filled in thewaveguide section of the optical package substrate, and thereafter anadhesive having a refractive index lower than the refractive index ofthe core material is used to attach the predetermined substrate to thewaveguide section.
 36. The optical device according to claim 35, furthercomprising a surface mounting type light receiving/emitting elementwhich is optically coupled to the optical waveguide defined in thewaveguide section through the optical path deflected by the optical pathdeflection section.